1. Field of Invention
The present invention relates to calibration of electronic devices. The invention is more particularly related to the calibration of delay lines or elements, particularly for use in test equipment or other devices in which precision time domain measurements are performed.
2. Discussion of Background
Typically, test instruments require calibration of delay lines done at the factory. The calibration is a test configuration that would provide stimulus and measure results on an oscilloscope, then a software program would create translations from the results to math functions that map the actual delay performance to desired performance. These mappings might take into account operational frequency, system operating temperature and other factors that effect performance. These mappings ultimately result in very complicated relationships that are based on assumptions about the behavior of the circuits. These usually produce some result that is stored in a memory on the instrument. Updates or changes to this result usually require that the instrument be shipped back to the factory for re-calibration. Also, variances in temperature and aging effects on components result in inaccuracies in the performance of the delay line functions in the test instrument.